Write ascii null value to a file using LittleFS

[mihirgraspberry]

Hi,

I am trying to update the firmware of ESP32 from a 4G module. I am able to download the file into 4G module. I am also able to read and print the contents of the binary file in ESP but unable to store the null characters inside the binary file into the ESP memory.

The actual binary file of ESP32 built with arduino contains several null characters. I am not able to write the null characters into the file.
The file write fails.
Is there a way we can write the ascii NULL character into the file.

I have used a hex editor to verify the presence of null characters inside the binary file.